Major Hurricane Lee (Category 3), Is Increasingly Likely To Impact Our Region Update One

548 

WTNT33 KNHC 120248

TCPAT3

BULLETIN

Hurricane Lee Advisory Number  27

NWS National Hurricane Center Miami FL       AL132023

1100 PM AST Mon Sep 11 2023

...LEE IS A LARGE MAJOR HURRICANE EXPECTED TO SLOWLY TURN

NORTHWARD LATER THIS WEEK...

...HAZARDOUS SURF AND RIP CURRENT CONDITIONS EXPECTED AT BEACHES

ACROSS THE WESTERN ATLANTIC ALL WEEK...

SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION

-----------------------------------------------

LOCATION...23.9N 64.8W

ABOUT 410 MI...655 KM NNW OF THE NORTHERN LEEWARD ISLANDS

ABOUT 580 MI...935 KM S OF BERMUDA

MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H

PRESENT MOVEMENT...WNW OR 295 DEGREES AT 7 MPH...11 KM/H

MINIMUM CENTRAL PRESSURE...948 MB...28.00 INCHES

WATCHES AND WARNINGS

--------------------

There are no coastal watches or warnings in effect.

Interests in Bermuda should monitor the progress of Lee.

DISCUSSION AND OUTLOOK

----------------------

At 1100 PM AST (0300 UTC), the center of Hurricane Lee was located 

near latitude 23.9 North, longitude 64.8 West. Lee is moving toward 

the west-northwest near 7 mph (11 km/h). A slow west-northwest to 

northwest motion is expected during the next day or two, followed by 

a turn toward the north by midweek. On the forecast track, Lee is 

expected to pass near, but to the west of Bermuda in a few days.

Maximum sustained winds are near 115 mph (185 km/h) with higher

gusts.  Lee is a category 3 hurricane on the Saffir-Simpson

Hurricane Wind Scale.  Some slight strengthening is forecast in the 

next day or so, followed by gradual weakening. 

Lee remains large with hurricane-force winds extending outward up 

to 80 miles (130 km) from the center and tropical-storm-force winds 

extending outward up to 185 miles (295 km). Saildrone 1064, located 

about 40 miles south-southeast of Lee's center, reported a sustained 

wind of 77 mph (124 km/h) and a wind gust of 105 mph (170 km/h) in 

the last few hours.

The estimated minimum central pressure is 948 mb (28.00 inches). 

Saildrone 1064 also reported a minimum pressure of 964 mb     

(28.46 inches) in the last few hours.

HAZARDS AFFECTING LAND

----------------------

Key messages for Lee can be found in the Tropical Cyclone Discussion

under AWIPS header MIATCDAT3 and WMO header WTNT43 KNHC and on the

web at hurricanes.gov/text/MIATCDAT3.shtml

SURF:  Swells generated by Lee are affecting portions of the Lesser

Antilles, the British and U.S. Virgin Islands, Puerto Rico,

Hispaniola, the Turks and Caicos Islands, the Bahamas, and Bermuda.

These swells are likely to cause life-threatening surf and rip

current conditions. Dangerous surf and rip currents have begun to

affect portions of the southeastern U.S. coast, and these conditions

are forecast to spread northward along much of the U.S. East Coast

during the next day or two. Please consult products from your local

weather office.

NEXT ADVISORY

-------------

Next complete advisory at 500 AM AST.

$$

Forecaster Papin

000

WTNT43 KNHC 120253

TCDAT3

Hurricane Lee Discussion Number  27

NWS National Hurricane Center Miami FL       AL132023

1100 PM AST Mon Sep 11 2023

This evening, Lee appears to be in the final stages of completing 

another eyewall replacement cycle (ERC). A GPM microwave pass at 

2201 UTC showed that the outer eyewall remains closed and, while it 

remains quite large, continues to contract slowly as the inner 

eyewall decays within. The initial intensity is held at 100 kt this 

advisory, blending the subjective and objective intensity estimates 

this evening. Another Air Force Reserve Reconnaissance mission is 

scheduled to investigate the storm overnight, and several saildrones 

along Lee's path are also likely to provide additional in-situ 

observations in the hurricane over the next day or so.

Lee continues to move slowly west-northwestward, with the motion 

estimated at 295/6 kt. Lee is expected to continue moving slowly 

west-northwest or northwest over the next 24-36 h while mid-level 

ridging remains in place centered northwest of the hurricane. 

However, the ridge should then become eroded and shift eastward as a 

mid- to upper-level trough swings into the northeastern United 

States. This pattern change should result in Lee turning northward 

and gradually accelerating. The biggest spread in the track 

guidance solutions remains in the along-track direction, with the 

GFS on the faster end, and ECMWF on the slower end. The NHC track 

forecast continues to favor a blend of the simple and corrected 

consensus aids, and is very close to the previous forecast track 

through 72 h, and is just a touch east of the prior track 

thereafter. On this track, Lee is likely to pass near, but west of, 

Bermuda late Thursday and Friday and then be situated offshore of 

the mid-Atlantic states and New England late Friday and Saturday.

With the pending completion of Lee's ERC, expected over the next 

6-12 hours, the NHC intensity forecast continues to show some modest 

re-intensification. This seems reasonable given that sea surface 

temperatures (SSTs) observed by a saildrone in Lee's south outer 

eyewall are still around 29 C. After the next day or so, however, 

coupled atmospheric-ocean models suggest the large wind field of Lee 

will begin to upwell cooler SSTs, and Lee is still forecast to move 

over a cool SST wake left behind by Hurricanes Idalia and Franklin 

later this week. In addition, the approaching mid-latitude trough 

should also result in an increase in shear, and dry air entrainment, 

which should result in more steady weakening later this week and 

over the weekend. This trough interaction will also ultimately lead 

to Lee transitioning to an extratropical cyclone by the end of the 

forecast period as it crosses the north wall of the Gulf Stream. The 

NHC intensity forecast is a bit lower than the prior cycle after 72 

h but remains close to the consensus intensity aids.

Although Lee is expected to weaken later in the week, it is still 

expected to significantly increase in size and hazards will extend 

well away from the storm center by the end of the forecast period.

KEY MESSAGES:

1. Dangerous surf and life-threatening rip currents will affect

portions of the northern Leeward Islands, the Virgin Islands, Puerto

Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas,

Bermuda, and most of the U.S East Coast through much of the week.

2. Lee could bring strong winds, rainfall, and high surf impacts to

Bermuda later this week. Interests there should continue to monitor

updates to the forecast of Lee during the next several days.

3. It remains too soon to know what level of additional impacts Lee 

might have along the Northeast U.S. coast and Atlantic Canada late 

this week and this weekend.  However, because wind and rainfall 

hazards will likely extend well away from the center as Lee grows in 

size, users should continue to monitor updates to Lee's forecast 

during the next several days.

FORECAST POSITIONS AND MAX WINDS

INIT  12/0300Z 23.9N  64.8W  100 KT 115 MPH

 12H  12/1200Z 24.4N  65.6W  105 KT 120 MPH

 24H  13/0000Z 25.0N  66.5W  105 KT 120 MPH

 36H  13/1200Z 26.1N  67.2W  100 KT 115 MPH

 48H  14/0000Z 27.5N  67.6W   95 KT 110 MPH

 60H  14/1200Z 29.4N  67.9W   90 KT 105 MPH

 72H  15/0000Z 31.6N  67.8W   80 KT  90 MPH

 96H  16/0000Z 37.6N  66.4W   70 KT  80 MPH

120H  17/0000Z 43.0N  66.0W   60 KT  70 MPH...POST-TROP/EXTRATROP

$$

Forecaster Papin

000

FXUS61 KCAR 120121

AFDCAR

Area Forecast Discussion

National Weather Service Caribou ME

921 PM EDT Mon Sep 11 2023

.SYNOPSIS...

A frontal boundary will move south across the Gulf of Maine

tonight. An occluded front will approach late Tuesday through

Tuesday night, then cross the region Wednesday through early

Thursday. High pressure returns on Friday. Hurricane Lee

slowly approaches south of the Gulf of Maine by Saturday.

Continue to monitor National Hurricane Center products for the

latest information on the strength/track/timing of Hurricane

Lee......

A frontal boundary will remain nearly stationary along the

Downeast coast early tonight. The frontal boundary will then

settle south across the Gulf of Maine overnight while low

pressure moves along the front. Expect numerous showers across

Downeast areas tonight. Shower chances diminish northward across

the remainder of the forecast area, with generally only cloudy

skies expected across northern areas. Also expect areas of fog

along the Downeast coast tonight through early Tuesday, with

patchy fog across the remainder of the forecast area. Low

pressure will lift northeast from the Great Lakes Tuesday,

drawing a cold/occluded front toward western New England late.

Moisture will persist in advance of the front keeping

cloudy/mostly cloudy skies across the forecast area, along with

the risk of isolated/scattered showers. Low temperatures

tonight will range from the lower to mid 50s north, to the upper

50s to around 60 Downeast. High temperatures Tuesday will range

from the mid to upper 60s north, to the upper 60s to around 70

Downeast.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...

Tuesday night expect an approaching well stacked system to be

pushing from Ontario into Quebec with a trailing warm occluded

front. A warm front will be over southern New England and will

remain over and south of the Gulf of Maine waters into Wednesday

AM. An approaching positively tilted trough will be digging over

the Great Lakes and shortwave energy will be rounding the bend

by late day. Warm and cloudy night with patchy fog expected Tue

Night into Wed AM with temps around 60F. Wednesday will feature

highs in the upper 60s to low 70s. By late day a rain band will

begin working into the FA from W to E ahead of the deep upper

500mb trof from the Great Lakes. Intially setting up over the

western zones before moving E through the night into Thu

morning. The upper trof will push through into Thursday morning

and take much of the day to get east of the area but the surface

front will move through in the AM. WPC continues a D3 excessive

rainfall outlook mainly in the "Marginal" category for much of

the FA except the Downeast coast. The "Slight" area makes it

into Northern Somerset county. Rainfall totals will be highest

along and northwest of the Longfellow Mtns where 1-1.5 inches

with isolated higher amounts are possible. Elsewhere, expecting

generally 0.5-1 inch but cannot rule out heavier amounts. Given

the soil moisture mainly in the 95th-99th percentile the chance

of isolated flooding remains possible especially in terms of

excessive runoff. This would mainly impact small creeks, streams

and urban areas. At this point widespread flooding isn`t likely.

&&

......LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...

Clearing skies over Central and Downeast areas with partly

cloudy skies across the north. Thursday night will be well

behind the cold/occluded front and upper trof with cooler

overnight low temps. Expecting Friday AM lows to be in the mid

to upper 40s north and low 50s south. High pressure ridging will

provide partly cloudy skies to the CWA on Friday for most of

the day with continued near seasonal normal high temps in the

upper 60s to low 70s.

High and mid clouds will then slowly spread S to N across the

FA Friday evening thru Saturday morning well in advance of Lee

as it continues to slowly move N across the western open

Atlantic. The consensus of long range models brings the western

periphery of the rain shield of Lee from SSE to NNW across the

FA beginning Sat afternoon and continuing Sat night into Sun

afternoon before any rain tapers to scattered showers Sun

afternoon with max PoPs capped at 50 percent over Downeast. The

actual track and impacts (if any) of Lee relative to our FA

remains under significant uncertainty at this time with a

considerable track spread by this coming weekend ranging as far

W from near Cape Cod MA and the Gulf of ME and as far E as Ern

NS. For now, we mention in the HWO to monitor latest NHC

advisories and forecast updates from this office as we approach

the weekend. There will be significant wave action due to long

period swells

Hazardous Weather Outlook

National Weather Service Caribou ME

344 PM EDT Mon Sep 11 2023

MEZ001>006-010-011-015>017-031-032-121945-

Northwest Aroostook-Northeast Aroostook-Northern Somerset-

Northern Piscataquis-Northern Penobscot-Southeast Aroostook-

Central Piscataquis-Central Penobscot-Southern Penobscot-

Interior Hancock-Central Washington-Southern Piscataquis-

Northern Washington-

344 PM EDT Mon Sep 11 2023

This Hazardous Weather Outlook is for Central Highlands Maine, Far

Eastern Maine, Far Northern Maine, Interior DownEast Maine, North

Woods Maine and Penobscot Valley Maine.

.DAY ONE...This afternoon and tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Locally heavy rainfall is possible for portions of the forecast area

from later Wednesday into Thursday morning, possibly resulting in

localized flooding.

Although the track, intensity, and impacts (if any) from Lee remain

uncertain at this time for our region, please monitor latest

National Hurricane Center advisories and forecast updates from WFO

Caribou heading into the weekend.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather

conditions according to Standard Operating Procedures.

$$

3:03 PM ADT Monday 11 September 2023

Tropical Cyclone Information Statement (Lee) in effect for:

Marine Zone

Maritime Waters

Browns Bank

East Scotian Slope

Georges Bank

LaHave Bank

Laurentian Fan

Sable

West Scotian Slope

This is the first official CHC information statement on Hurricane Lee.

The next information statement will be issued by 3 p.m. ADT Tuesday.

Lee could impact weather in Atlantic Canada this weekend as it moves northward from the tropics.  This initial bulletin is anchored to the offshore marine district south of Nova Scotia where the circulation of Lee would encroach upon first.

We are starting to get a better idea of how the weather will evolve this week over Atlantic Canada and the role Hurricane Lee may play.  Once the hurricane makes a northward turn by late Wednesday it will further enhance the tropical airmass over Atlantic Canada.  It will also have the effect of slowing the progress of a front which could increase the risk of heavy rainfall over the Maritime provinces during the latter part of the week.

We expect Lee's circulation to broaden significantly as it moves north later this week and there are no indicators at this time that the storm will be re-invigorated through merging with non-tropical weather systems.  Also it is possible the forward motion of the storm could slow which would permit further weakening over cooler waters before affecting land.  Given these factors, the storm would approach the region as a weak hurricane or strong tropical storm.  The range of track possibilities is very broad this far ahead in time, ranging from somewhere in Maine to the southeast of Nova Scotia.   

With the expanding size of the hurricane and a long trajectory northward, building surf conditions and rip currents are expected along the Atlantic coast of Nova Scotia this week and particularly on Friday.

This bulletin will be updated tomorrow with the latest forecast rationale.

Forecaster: Fogarty

Please continue to monitor alerts issued by the Canadian Hurricane Centre and forecasts issued by Environment Canada.